Roberta Guglielmino

Extranodal γδ-T-cell lymphoma in a dog with leishmaniasis

An 8-year-old intact male mongrel dog with alopecia and weight loss was referred to the Veterinary Faculty of Naples. The dog had pale mucous membranes, enlarged prescapular lymph nodes, and splenomegaly. Laboratory abnormalities included anemia, thrombocytopenia, and hyperglobulinemia. Bone marrow aspirate smears contained numerous Leishmania amastigotes and an immunofluorescent antibody titer was strongly positive (1:1280) for leishmaniasis. The dog was treated with a combination of meglumine antimoniate and allopurinol for 60 days and showed clinical improvement. Two months after the end of treatment the dog was again referred because of relapse of leishmaniasis and the presence of a firm subcutaneous mass on the medial right thigh. Based on cytologic examination of fine needle aspirates of the mass, a diagnosis of large-cell lymphoma was made. Flow cytometry of tumor cells revealed gammadelta-T-cell lymphoma with a CD5+, CD3+, TCRgammadelta+, CD4-, CD8-, CD45RA+ immunophenotype. Using nested PCR, amastigotes were not detected in the neoplastic tissue. An association between leishmaniasis and hematopoietic tumors has been described rarely. gammadelta-T cells may be involved in the host response to this parasite, and prolonged antigenic stimulation and chronic immunosuppression (typical of leishmaniasis) play a crucial role in the etiopathogenesis of T-cell lymphoma.

Clinical Usefulness of Peripheral Blood Lymphocyte Subsets in Canine Lymphoma

The classification of canine lymphoid malignancies into groups based on cell of origin (Bor T-cell types) is possible with immunophenotypic analysis. A high frequency of B-cell lymphomas has been described; about 30% of lymphomas are of T-cell origin (Teske et al., 1994a; Fournel-Fleury et al., 1997; Grindem et al., 1998). In human medicine the major diagnostic role of blood lymphocyte subset typing is the screening for non-Hodgkin’s lymphomas with peripheral blood involvement and their differentation from reactive lymphoproliferative conditions (Thalhammer-Scherrer et al., 2000). The aim of this project is to evaluate the diagnostic efficacy of blood immunophenotyping in dogs with lymphoma in order to detect the blood involvement and the prognostic benefits.

Effects of Interferon Alpha (INF-α) Therapy on Peripheral Blood Lymphocyte Subsets from FIV and FeLV Naturally Infected Cats

Lymphocyte depletion is assessed as a central event in the pathogenesis of FIV infection, whereas the data regarding FeLV infection are insufficient and sometimes conflicting (Novotney et al., 1990; Tompkins et al., 1991; Hoffmann-Fezer et al., 1996). The therapy is basically symptomatic and an effective specific therapeutic protocol has not yet been determined. On the basis of results from various studies (Cummins et al., 1988; Zeidner et al., 1990; Weiss et al., 1991), INF-a could have a role in such a protocol. The purpose of this study was to evaluate the effects of INF-a on peripheral blood lymphocyte subsets and clinical signs in naturally FIVor FeLV-infected cats, pointing out possible correlations between the two aspects.